This section is intended to introduce the reader to various aspects of the art that may be related to various aspects of the present invention. The following discussion is intended to provide information to facilitate a better understanding of the present invention. Accordingly, it should be understood that statements in the following discussion are to be read in this light, and not as admissions of prior art.
Network Load Balancing (NLB) Algorithm is existing 1x-EV-DO Advanced concept that provides methods of off-loading traffic from the more loaded radio cells to the less loaded cell, by manipulating allowed forward link cells for every active connection but only on (one) connected frequency.
Current implementation of NLB considers traffic load on every sector in the terminal's active set (A_SET) and intelligently offloads a sector that is more loaded by moving active/connected users' serving Down-Leg (DL) to the other sectors in the A_SET that are less loaded. This improves user's forward link throughput as it is moved to the sector with less contention for the forward link scheduler-resources.
The CDMA radio network can be viewed as a two dimensional space consisting of sectors in the horizontal plane and frequencies in the vertical plane. A CDMA radio-connection must be on the same frequency, as a terminal has only one transmitter, so connection A_SET is managed across the sector/horizontal plane.
FIG. 1 depicts that arrangement. FIG. 1 shows radio resources in CDMA network.
Hence, loading imbalances are possible not only across the different sector of a base station (BTS), but also across the frequencies collocated on the same BTS.
Today, there are solutions that manage                load across sectors in connected state (NLB) AND        access to a collocated carrier (MCTA).        
However with data connections expected to last longer as new real-time applications are constantly emerging, a solution is needed to extend offload decisions of the connected users into vertical/frequency plane as well (i.e. not just across the sector of the A_SET on the connected frequency, but also across other frequencies collocated in the area).
The proposed solution extends load balance to the frequency plane, while terminals are in the connected state.
In the current implementation offload for connected users is done only to the cells in the active set that are on the same frequency.
There is no solution for offload to a different frequency, for already connected users.